In the interest of keeping the debate over climate change rational and civil, I would like to clarify the positions of the climatologist Roy Spencer and John Christy, who were cited in John McClaughry’s letter of July 5 rebutting one by Mitch Goldfarb on June 26.

The satellite measurements of global temperature shown on Spencer’s website (www.drroyspencer.com/latest-global-temperatures) show a rising trend in temperature since 1979 consistent with other data showing global warming. There are large fluctuations in their results, however, which are presumably caused by natural phenomena. These fluctuations suggest to Spencer and Christy that the rising trend is also due to some unknown natural phenomenon, rather than to human causes.

Spencer and Christy believe that since the global warming is natural, there is nothing people can or should do about it. This is in contrast to the consensus view that long-term global warming has human causes, which if not corrected will have catastrophic consequences in the future.

Which of these two views is correct can only be determined by scientific research, not by politics. Either way the consequences will be obvious in a few decades, by which time the verbal barbs between left and right will seem pretty silly.